1. Field of the Invention
The present invention relates to a surface light source device, a method of manufacturing the surface light source device and a liquid crystal display (LCD) apparatus having the surface light source device. More particularly, the present invention relates to a surface light source device capable of improving lifetime and optical characteristics, a method of manufacturing the surface light source device and an LCD apparatus having the surface light source device.
2. Description of the Related Art
In a liquid crystal display (hereinafter, referred to as LCD) apparatus, generally, the arrangement of liquid crystal molecules is varied in response to an electric field applied thereto, and thus a light transmittance thereof is changed.
A conventional LCD apparatus displays an image containing information by using the liquid crystal. The LCD apparatus has various merits for example, such as high luminance, high efficiency, uniform luminance, long lifetime, thin thickness, light weight and low cost and so on, so that the LCD apparatus is used for a portable computer, a communication apparatus, a television receiver set, etc.
The LCD apparatus is a light receiving type display apparatus, so that the LCD apparatus requires a light supplying part.
The light supplying part includes a plurality of cold cathode fluorescent lamps (hereinafter, referred to as CCFL) having a rod shape or a plurality of light emitting diodes (LED) having a dot shape. The CCFLs have various merits, for example, such as high luminance, long lifetime, white color and so on. The CCFLs also generate lower heat than incandescent lamps. The LEDs also have high luminance and low power consumption.
The light supplying part having the CCFLs or LEDs requires optical members such as a light guide plate (LGP), a light diffusion plate (LDP), a brightness enhancement sheet (BES), etc., because the CCFLs and LEDs don't have uniform luminance. Therefore, the volume and weight of the LCD apparatus are increased.